Propeller hub



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Sept. 19, 1933- w. LAMBERT 1,927,592

PPPPPPPPPP UB Filed May 24. 1932 y 2 Sheets-Sheet 2 INVENTOR.

Patented sept. 19, 1933 UNITED STATES PATENT OFFICE PROPELLER HUB Chandley William Lambert, Cleveland, Ohio Application May 24, 1932.' Serial No. 613,220

9 Claims. (Cl. 17o-163) The invention relates to improvements in propeller hubs, in which rotatably mounted blades can be turned for the purpose of controlling the pitch of the blade while in flight. One form of the invention is shown in the accompanying drawings, in which Fig. 1 is a longitudinal crosssection through the center line of the hub and blade shank and in a plane which includesv the centerline of the drive shaft.

$ Fig. 2 is a half section on line 2--2 of Fig.

` 8 8, which is further secured by a bolt through locking lugs 16, which bolt spans a narrow vertical cut 24 in the wall of hub 2. Nut 9 on shank 4 takes the end thrust due to centrifugal force acting on blade 10 and shank 4.

Blade 10 is pivoted in shank 4 by pin 11 which spans recess 22 in shank 4 in the region of the side 4bearings 5-5, preferably with the center of the pivot pin 11 midway between the spaced annular ball side bearing ball races 17--17 and 3 ls-ia.

Compression spring 23, recessed in shank 4, bears against ball 20 which contacts cams 21-21 on blade l0, for the purpose of holding blade 1() in an upright position when at rest.

In Fig. 2, hub 2 is secured to shaft 1 by nut 3. 4 is the shank, 5 the annular side bearing, 10 the formed stem end of the blade pivoted on pin 11 and recessedv into shank 4. Nut 9 is on shank 4, into which square projection l2 of .40 wheel 14, is tted. Radial arm 15; secured -to wheel 14 which is rotatable in annular bearings 13-l3; projects outwardly through a closed slot in hub 2, and has a rearwardly extending push-'- pull rod 26, pivoted to it at 25. This is a means for rotating shank 4 and blade 10 in hub 2 for the purpose of changing the pitch of blade l0.

When the shaft isrevolving, thrust of blade 10 causes the blade to lean forward toward the position 10A, and revolve in a wide cone. Centrifugal force acting on blade 10, tends to cause blade 10 to revolve in a plane at right angles to the center line of drive shaft 1. The resulting forward pull on the hub is straight forward from the center of pin 11 as indicated by the w heavy arrow in the drawings, Fig. 1. This produces no warping in side bearing 5 5, because the pressure on balls 17 and 18 is approximately the same.

This accomplishes one object of the invention which is to reduce the power ordinarily necessitated for pitch changing while in night.

Anotherobject is the reduction of propeller noise due to vibration of a rigid blade.

1. A shaft, a radial hub secured to said shaft, spaced annular bearings cooperating with said hub, a propeller blade shank cooperating with said bearings, a transverse pivot located between said bearings on said shank, a propeller blade mounted on said pivot, and means for rotating said shank relatively to said hub, flexible dampening means cooperating with said blade and said shank.

2. A power shaft, a hollow radial hub secured to said shaft, annular side and thrust bearings within said hub, a threaded holding ring securing said bearings within said hub, means tightening said hub to further secure said ring, a shank positioned coaxially with said hub and cooperating with said bearings, means cooperating with the inner end of said shank for rotating said shank relatively to said hub, a recess in said hub within the region of said bearings, a transverse pin positioned within said recess, a pro-Q peller blade mounted on said pin, flexible means cooperating with said blade and said shank for holding said blade in a radial position relatively to said shaft when said blade and said shaft are at rest.

3. A radial propeller hub, spaced annular bearings within said hub, a rotatable propeller blade shank pivoted concentrically to said hub, a propeller blade transversely pivoted to said shank, said pivot of said blade to said shank positioned within a recess in said shank and also Within said bearings in said hub, means for rotating said shank relatively to said hub, cams on the stem end of said propeller blade within said shank recess, a compression spring within said recess, said spring cooperating with said cams. .100

4. A propeller hub, a shank rotatable in saidl hub, a recess in said shank, a propeller blade transversely pivoted to said shank, the pivot of said blade to said shank positioned within said recess in said shank and also within the said hub, means for rotating said shank for the purpose of changing the pitch of said blade.

5. A drive shaft, a hub secured to said shaft, spaced bearings within said hub, a propeller blade shank rotatable in said bearings, a rece in said shank, a propeller blade pivoted to said shank, the pivot positioned transversely Within said recess in said shank and also within said bearings in said hub, means for rotating said shank, ilexible means for holding said blade coaxially with said shank when said blade is at rest.

pitch of said blade, flexible means for holding said blade in a radial position when at rest.

7. A hollow hub secured to a powex` shaft, annular side and thrust bearings cooperating with said hub and a shank positioned coaxially with "Ill said hub, a recessed opening in the endof said shank remote from said shatt, a propeller blade transversely pivoted to said shank Within said recessed opening, means for rotating said shank.r

8. A rotatable shank mounted coaxially with a propeller hub, a blade pivoted transversely to said' shank, means for holding said blade coaxially with said shank when said blade is at rest, means for rotating said shank relatively to said hub.

9. A shaft,4 a hub secured to said shaft, bearings cooperating with said hub, a propeller shank rotatable in said bearings, a recess in said shank positioned within said bearings, a pin cooperating with said shank transversely of said recess, a propeller blade cooperating with said pin, spaced cams secured to said blade, exible pressure means cooperating with said cams, a rotatable wheel cooperating with said shank, means for rotating said wheel substantially as specified.

CHANDLEY WILLIAM LAllmERT. 

